Background: Diabetes is a risk factor for postoperative complications. Previous meta-analyses have shown that elevated glycated hemoglobin (HbA1c) levels are associated with postoperative complications in various surgical populations. However, this is the first meta-analysis to investigate the association between preoperative HbA1c levels and postoperative complications in patients undergoing elective major abdominal surgery. Methods: PRISMA guidelines were adhered to for this study. Six databases were searched up to April 1, 2020. Primary studies investigating the effect of HbA1c levels on postoperative complications after elective major abdominal surgery were included. Risk of bias and quality of evidence assessments were performed. Data were pooled using a random effects model. Meta-regression was performed to evaluate different HbA1c cut-off values. Results: Twelve observational studies (25,036 patients) were included. Most studies received a ‘good’ and ‘moderate quality’ score using the NOS and GRADE, respectively. Patients with a high HbA1c had a greater risk of anastomotic leaks (odds ratio [OR]: 2.80, 95% CI [1.63, 4.83], P < 0.001), wound infections (OR: 1.21, 95% CI [1.08, 1.36], P = 0.001), major complications defined as Clavien-Dindo [CD] 3–5 (OR: 2.16, 95% CI [1.54, 3.01], P < 0.001), and overall complications defined as CD 1–5 (OR: 2.12, 95% CI [1.48, 3.04], P < 0.001). Conclusions An HbA1c between 6% and 7% is associated with higher risks of anastomotic leaks, wound infections, major complications, and overall postoperative complications. Therefore, guidelines with an HbA1c threshold > 7% may be putting pre-optimized patients at risk. Future randomized controlled trials are needed to explore causation before policy changes are made.

Humans ; Female ; Mastectomy, Segmental ; Margins of Excision ; Reoperation ; Breast Neoplasms/surgery* ; Retrospective Studies ; Carcinoma, Ductal, Breast/surgery* ; Neoplasm Recurrence, Local

INTRODUCTION: Image-guided thermal ablation, preferably with ultrasonography (US), is increasingly used for treatment of small liver tumours. Perfluorobutane-contrast-enhanced US (pCEUS) is a promising tool that may allow for targeting of tumours that are otherwise imperceptible on greyscale US. Although pCEUS has been reported to be effective, the literature has been limited outside of Japan and South Korea. We aimed to provide data that supports the use of pCEUS in the thermal ablation of sonographically occult liver tumours. METHODS: We conducted a retrospective single-centre study of 35 consecutive patients who underwent pCEUS-guided ablation of 48 liver tumours with a median size of 1.2 cm. Periprocedural, one-month post-treatment and relevant follow-up imaging studies were reviewed. Electronic records were also obtained, with long-term follow-up data of 12-28 months being available for 32 patients. RESULTS: 36 (75%) tumours that were imperceptible on greyscale US became visible with pCEUS. Overall, complete tumour ablation at one month was 89%. 1 (3%) patient developed a major complication following treatment, while 6 (17%) had minor post-treatment complaints. The local tumour progression rate was 17%, with a median time of 14 months. CONCLUSION pCEUS has a role in US-guided thermal ablation of liver tumours, offering a high technical success rate that is comparable to reported data. Additional benefits may include improved procedural time and freedom from ionising radiation.